Troubleshooting “Fixed Disk Error” at Boot Which of the following is the most likely cause of a BIOS “fixed disk error” during startup on a legacy PC?

Introduction / Context:
Old BIOS firmware relied on manual CMOS setup for fixed disk (hard drive) geometry and mode. If these settings were wrong or the battery failed, boot could halt with a “fixed disk error.” Understanding this helps isolate boot failures on legacy systems.

Given Data / Assumptions:

• Legacy BIOS with manual drive configuration (CHS/LBA, drive type).
• “Fixed disk” refers to hard drives, not optical media.
• Symptoms occur during POST or initial boot handoff.

Concept / Approach:

Incorrect CMOS settings for the hard disk (geometry, translation, enabled/disabled, master/slave) commonly trigger “fixed disk error.” A dead CMOS battery can also revert settings. CD-ROM presence is unrelated to the hard drive error, and RAM timing issues usually produce memory errors, not “fixed disk” errors.

Step-by-Step Solution:

Verification / Alternative check:

After fixing CMOS parameters, the drive should pass POST and allow the OS loader to proceed. Drive detection screens will list correct model and capacity.

Why Other Options Are Wrong:

CD-ROM not installed: Optical drives do not cause “fixed disk” errors. Incorrect RAM settings: Typically yield memory test failures or system instability, not a fixed-disk-specific message. All of the above: Incorrect because not all listed items can cause this specific error.

Common Pitfalls:

Replacing the HDD before verifying CMOS; overlooking cable orientation; forgetting to save BIOS changes; ignoring failing CMOS batteries that lose settings between boots.

Final Answer:

Incorrect CMOS settings